I. Field
The present disclosure relates generally to electronics, and more specifically to a receiver.
II. Background
A wireless communication device (e.g., a cellular phone) may operate in a wireless communication system utilizing frequency division duplexing (FDD). The wireless device may support full-duplex operation and may be able to simultaneously transmit and receive data for two-way communication. The wireless device may include a transmitter and a receiver coupled to a primary antenna. For data transmission, the transmitter may modulate a radio frequency (RF) carrier signal with data to obtain a modulated signal and may amplify this modulated signal to obtain a transmit (TX) signal having the proper signal level. The TX signal may be routed through a duplexer and transmitted via the primary antenna to a base station. For data reception, the receiver may obtain a receive (RX) signal via the primary antenna and the duplexer. The receiver may condition and process the RX signal to recover data sent by the base station.
The wireless device may include a diversity (DRX) receiver coupled to a diversity/secondary antenna. The diversity receiver may obtain a secondary RX signal via the diversity antenna and may condition and process the secondary RX signal to recover data sent by the base station. The diversity receiver may help mitigate multipath and fading and may also help to cancel interference from other systems on the same frequency. The diversity receiver may improve end user experience by increasing download speed and power and may also provide other advantages.
In full-duplex operation, the circuitry within a receiver may observe interference from a transmitter. For example, a portion of the TX signal may leak from the transmitter to the diversity receiver, and the leaked TX signal may cause interference to a desired signal within the secondary RX signal. The TX signal and the desired signal typically reside in two different frequency bands for a FDD system. Hence, a receive (RX) filter may be used in the diversity receiver to pass the desired signal and to attenuate the leaked TX signal.
The wireless device may be capable of communicating with different wireless systems and/or may support operation on multiple frequency bands. These capabilities may allow the wireless device to receive communication services from more systems and enjoy greater coverage. The wireless device may have multiple receive paths in a receiver for all frequency bands and systems supported by the receiver. Each receive path may include a set of circuit blocks such as an RX filter, a low noise amplifier (LNA), etc. The circuit blocks for each receive path may be designed specifically for the frequency band(s) and/or the system(s) supported by that receiver path. The wireless device may have many receive paths and many circuit blocks in order to support multiple frequency bands and/or multiple systems. These many receive paths may increase the complexity, size, cost and/or power consumption of the wireless device, all of which may be undesirable.